(a) Field of Disclosure
The present disclosure of invention relates to a display device, and more particularly, to a display device having a gate driver monolithically integrated as part of a substrate of the display device.
(b) Description of Related Technology
Among image display devices, a liquid crystal display (LCD) is one of the flat panel displays that have gained wide usage. The typical LCD includes two display substrates in which there are provided field generating electrodes such as pixel electrodes and a common electrode, etc. The two display substrates are typically provided in spaced apart facing relation and a liquid crystal material layer is interposed therebetween. Electronic circuit portions of the liquid crystal display apply voltages to the electric field generating electrodes to thereby generate electric fields extending through the liquid crystal material layer. As a result, an orientation direction of liquid crystal molecules of the liquid crystal material layer is determined and polarization of incident light is controlled. This ultimately results in display of a desired image. Other types of falt panel display devices include an organic light emitting device (OLED), a plasma display device, and an electrophoretic display, etc. in addition to the liquid crystal display.
The typically display device includes a gate lines driver circuit and a data lines driver circuit. In one variation, the gate lines driver circuit is monolithically integrated as part of a lower or TFT array substrate along with a plurality of gate lines, data lines, thin film transistors, etc. Since the functionality of the so-integrated gate lines driver is provided on board the TFT array substrate, it is no longer required to provide and mount an additional, separate gate lines driving chip and thus it is possible to save on manufacturing costs and increase device reliability. However, the monolithically integrated gate lines driver has drawbacks. One of the problems is that electronic characteristics of a semiconductive portion (and in particular, an amorphous semiconductor material, e.g., Si(a)) of the thin film transistor change according to temperature and is susceptible to noise problems at higher temperatures. As a result, a gate drive voltage signal that is output at high temperatures by conventional, monolithically integrated gate lines drivers does not have a desired waveform (e.g., an ideal square wave shape free of noise) and instead, interfering noise spikes may occur.
The above information disclosed in this Background section is only for enhancement of understanding of the technology and therefore it may contain information that does not form part of the prior art that is already known to persons of ordinary skill in the pertinent art.